Over the last decade, a number of concerns have arisen related to safety issues regarding paramyxovirus vaccines that have had an adverse effect on the public's trust. These concerns affect not only parents whose children are the primary recipient of childhood disease vaccines, but also ranchers devoted to raising animals susceptible to various types of paramyxoviruses.
Historically, Newcastle disease has been a devastating disease of poultry, and in many countries the disease remains one of the major problems affecting existing or developing poultry industries. Even in countries where Newcastle disease may be considered to be controlled, an economic burden is still associated with vaccination and/or maintaining strict biosecurity measures. The variable nature of Newcastle disease virus strains in terms of virulence for poultry and the different susceptibilities of the different species of birds mean that for control and trade purposes, Newcastle disease requires careful definition. Confirmatory diagnosis of Newcastle Disease requires the isolation and characterization of the virus involved. Currently Newcastle disease control is limited to prevention of introduction and spread, good biosecurity practices and/or live attenuated virus vaccination. Newcastle disease viruses may infect humans, usually causing transient conjunctivitis, but human-to-human spread has never been reported. Alexander D. J., “Newcastle disease and other avian paramyxoviruses” Rev Sci Tech. 19(2):443-62 (2000).
Historically, the live attenuated measles virus (MV) vaccine and the combination multivalent measles, mumps, and rubella (MMR) vaccine have had a positive impact on the health of children worldwide by preventing infectious disease. The induction of an effective antiviral immune response using these live attenuated virus vaccines, however, are known to result in a significant rate of adverse events (i.e., for example, autism). Kennedy et al., “Measles virus infection and vaccination: potential role in chronic illness and associated adverse events” Crit Rev Immunol. 24(2):129-56 (2004).
Healthy, and at risk, children are susceptible to the morbidity and mortality associated with viral-induced respiratory diseases, including respiratory syncytial virus (RSV) and influenza. Currently, the World Health Organization is attempting to develop and distribute effective vaccines to prevent/reduce key viral respiratory diseases. The progress, however, is slow and the risk/benefit ratio is high. A vaccination program for viral respiratory infections should include the prevention of lower respiratory tract infections and prevention of infection-associated morbidities, hospitalization and mortality. Presently, there are two influenza vaccines; i) a trivalent inactivated vaccine, and ii) a live, cold-adapted, attenuated vaccine. Compliancy, however, is relatively low (i.e., 10-30%). Because it is believed that the low compliancy is related to the known high risk of contaminated vaccines, those in the art recommend that research should continue into safe and effective vaccines for all childhood viral illnesses. Greenberg et al., “Immunization against viral respiratory disease: A review” Pediatr Infect Dis J. 23(11 Suppl):S254-61 (2004).
What is needed in the art is a low risk, highly effective paramyxovirus vaccine that is compatible with population-wide distribution marketing goals of low cost and high production rates.